Called Superman Memory Crystal, researchers have developed a specially structured quartz glass which can be used to store data in quite high density and more importantly in a form which is nearly indestructible. They make use of a property of the quartz crystal which splits light traveling through the media along two different possible paths depending on the direction and polarization of the light, which can be controlled and used to write information to the crystal. More importantly the write method is a femtosecond laser pulse, which means that you can write data very quickly, a hurdle that has been difficult for other long term high capacity storage solutions other researchers have been developing. Drop by The Register for links to more technical explanations.

"Southampton Uni research boffins have demonstrated access to pulsed femtosecond laser-written data bits in fused nano-structured quartz glass, which can store the data for a practically unlimited time."